Ok MCRider, so I have a theory.
Rich condition, cylinder doesn't fire, traditionally one would hear "gas washed" cylinder/rings possible damage, does oil smell like gas ?
Theory: When the cylinder doesn't fire, the usual marked increase in pressure from explosion in the already compressed pressure chamber driving the piston downward, does not occur.
We have a lower pressure there than a properly firing cylinder.
This lower pressure results, as the strokes go on, on an intake air takeup block by back pressure on the exhaust valve from the ex manifold/pipe area burning the gas, in oil blowing upward past the rings, exiting through the exhaust valve, and burning with the gas and oil richened hot exhaust, causing the white smoke.
I could have said that better, hope you caught my thinking.